Construction of triangle from side $c$ and heights $h_a, h_b$

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I want to construct a triangle $\Delta(A,B,C)$ with given side $c$ and heights $h_a, h_b$. To construct the triangle means to use only ruler and compass. How can I solve this?

I started as follows:

$1)$ Given the side $c$ with endpoints $A,B$, we can construct the circle with diameter $\overline{AB}$.
$2)$ We can draw a circle with center $A$ and radius $h_a$ and get a Point $F$ as intersection point. My hope is now that the line segment $\overline{AF}$ will become our height $h_a$.

So the third point $C$ has to lie on the line $BF$ such that the height $h_b$ will be the given one. But how can I achieve this?

Best regards

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Yes, we have $\overline{AF}=h_a$.

Now, draw another circle with center $B$ and radius $h_b$. Then, you can get a point $G$ which is the intersection point of this circle with the circle with diameter $\overline{AB}$. Here, we have $\overline{BG}=h_b$.

Then, note that $C$ is the intersection point of the line $AG$ with the line $BF$.


Added : The construction depends on the relation between $h_a^2+h_b^2$ and $c^2$.

  • If $h_a^2+h_b^2=c^2$, then $F=C$.

  • If $h_a^2+h_b^2\lt c^2$, then $C$ is the intersection point of the line $AG$ with the line $BF$.

  • If $h_a^2+h_b^2\gt c^2$, then $C$ is the intersection point of the line $AF$ with the line $BG$.